This disclosure generally relates to optimization of aircraft assembly line operations.
The basic principle of a lean production system is to manufacture in the most economical way possible. This is accomplished by focusing on meeting customer requirements, such as determining production time. One of the elements of lean production is producing to takt time. Takt time is the rate in time that a plant maintains to meet customer demand. For example, in aircraft manufacturing, aircraft are assembled on a line, and are moved on to the next station after a certain time, i.e., the takt time. The time to complete work on each station has to be less than the takt time in order for the product to be completed within the allotted time. The takt time concept aims to match the pace of production with customer demand and the net available work time available. Takt time is commonly used in assembly lines that move a product along a line of stations that each perform a set of predefined tasks.
In accordance with a known method of assembling an aircraft, a fuselage is first equipped with internal components at respective work stations of a first assembly line and then is equipped with external components at respective work stations of a second assembly line that is downstream from the first assembly line. (Alternatively, the first and second assembly lines may be respective portions of a single assembly line.) It is known to set up the first and second assembly lines in one building. In the alternative, a single building may house multiple assembly lines for installing internal components and multiple assembly lines for installing external components. In general, a single building may house M assembly lines for installing internal components and N assembly lines for installing external components, where M and N are positive integers that are not necessarily equal.
The operations whereby internal components, such as wires, plumbing, seats, storage bins, carpets, stairs, galleys, closets, etc., are installed inside a fuselage are sometimes referred to as “fuselage stuffing”. During fuselage stuffing operations, the inventory of internal components awaiting installation is stored next to the assembly lines for installing internal components. This inventory occupies valuable floor space next to those lines, and causes the assembly lines for installing external components to move slower than need be, because there is more work to do on the upstream assembly lines for installing internal components.
It would be desirable to reconfigure such aircraft assembly facilities in a manner that enables an increase in the rate at which aircraft are assembled (i.e., a decrease in the takt rate).